1. Field of the Invention
This invention relates to a disc changer device. More particularly, it relates to a disc changer device in which a disc is transported as it is held from the direction of disc thickness.
2. Description of the Related Art
A recording disc as a recording medium for information signals, such as an optical disc or a magneto-optical disc, has so far been proposed. This recording disc has a disc-shaped disc substrate and a signal recording layer deposited thereon.
A disc player apparatus for recording/reproducing information signals for the recording disc has been proposed. This disc player apparatus includes a disc driver having a rotational mechanism for holding and rotating the recording disc and an optical pickup device for writing/reading information signals to the signal recording layer of the recording disc rotationally driven by the rotational mechanism. The optical pickup device includes a semiconductor laser as a light source and an objective lens for condensing the light beam emanated by the semiconductor laser on the signal recording layer of the recording disc.
A disc changer device has so far been proposed, in which plural recording discs are housed in a stacked state, and an optional one of these discs is selected from these discs for loading on the disc driver for recording/reproducing the information signals for the loaded recording disc. Such disc changer device includes a disc stocker for housing therein a number of recording discs in a stacked state and a disc loading mechanism for taking out and transporting the selected recording disc from the disc stocker for loading on the disc driver.
Such a disc loading mechanism has so far been used which has a gripper for gripping one of the recording discs housed and held in the disc stocker. The gripper is designed to be moved from the disc stocker to a position in register with the disc driver.
In such disc changer device, it has been desired to increase the number of recording discs housed therein without increasing the size of the device. To this end, it is necessary to reduce the distance between the recording discs housed and held in a stacked state in the disc stocker.
However, if the distance between the recording discs in the disc stocker is reduced, it becomes difficult to fabricate the gripper inserted into the space between the discs housed within the disc stocker for taking out the recording disc from the stocker. That is, for gripping the desired one of the recording discs housed within the disc stocker, a disc holding portion needs to be inserted into the space between the neighboring discs on both sides of the major surfaces of the desired disc. If the neighboring discs are positioned close to the optional disc for increasing the number of the recording discs that can be housed within the disc stocker, the disc gripping portion of the gripper needs to be reduced in size, such that it becomes impossible to assure a sufficient mechanical strength of the disc gripping portion of the gripper.
Although it may be contemplated to push the recording disc taken out of the disc stocker by a thin member, such as a pin, from the opposite side to the gripper of the disc stocker, the disc loading mechanism tends to be increased in size and complex in structure as compared to the above-mentioned device constructed solely by the gripper.
If the distance between the recording discs held by the disc stocker is reduced, the recording disc taken out from the disc stocker is likely to come into sliding contact with the neighboring recording discs left in the disc stocker to destruct the discs.